1. Field of the Invention
The present invention essentially relates to a process for curing pipe insulation, comprising the employment of a two-part mold and to the utilization of a device for the passage of curing air through the mold and through a pipe insulation preform which is arranged around a core disposed within the mold.
2. Discussion of the Prior Art
A process for the production of insulating sleeves for conduits or pipe members is disclosed in German Laid-Open Patent Appln. No. 1 525 860. In that instance, two cooperating, complementary die or mold halves are adapted to produce a pipe insulation consisting of either a single layer or plurality of layers of an insulating material, such as a synthetic fibrous wool-like material which is impregnated with a synthetic resin. The mold halves are essentially identical in nature and press rolled matting of this insulating material into suitable pipe insulation structure. There is no structure provided which will prevent the formation of burrs.
Stephens et al U.S. Pat. No. 2,778,759 discloses a thermal pipe insulation constituted of a substantially flexible material, wherein the resilience of matting which is rolled into a cylindrical pipe-shaped form enables a pair of cooperating mold halves to apply air pressure to the interior of the resilient material so as to enable the formation of the finished pipe structure, The mold halves are essentially identical in configuration and are clamped together to form the pipe construction from the flexible or resilient material which is of a wool-like texture.
A disadvantage of Stephens et al. resides in that it is impossible to prevent the formation of burrs on the outer surface of the chute which is formed by the wool-like material at the plane in the juncture between the mold halves. The mold halves are unable to make full contact with each other due to the burrs formed by the wool materials spreading between contacting mold plans. Consequently, the process in Stephens et al. would not be satisfactory for forming insulating chutes in a manner analogous contemplated by the inventive process.
Finally, Gullich U.S. Pat. No. 2,127,404 relates to a process and apparatus in which cooperating mold halves are adapted to press powder materials into tablets with a concurrently shearing of the end surface of the pressed material into predetermined tablet thicknesses to provide discrete pressed tablet structures. There is no disclosure of any process for the curing of insulating chutes in a manner analogous to that contemplated by the present invention.